An antenna is an essential component in wireless communication. As the demand for the amount of wirelessly transmitted data increases, the availability of a large bandwidth, such as a 7 GHz bandwidth for the 60 GHz band millimeter-wave communication, allows for a wide variety of applications in recent years. For instance, a millimeter-wave signal transceiver module may be disposed in a hand-held electronic device so that the hand-held electronic device may perform a high-speed wireless transmission through the millimeter-wave channel.
Currently, most of hand-held electronic devices adopts a unibody metal chassis, such that positions for installing a millimeter-wave antenna are further restricted. Moreover, the millimeter-wave signal may be resonantly and transversely transmitted inside of a metal cavity to reduce a radiation efficiency of the antenna. In case the small hand-held electronic device, such as a smart phone, includes multiple modules, components and antennas corresponding to various communication standards, when it comes to dispose a millimeter wave module into the already limited space, several problems may arise including spatial and functional interferences as well as the heat dissipation caused by the new installed millimeter wave module. It should also be noted that the millimeter wave antenna should not be blocked by user's hands when holding or operating the device. In short, for the millimeter wave module applied to consumer electronic products, many considerations including antenna gain, beam orientation and field of coverage, module's total volume, as well as manufacturing and assembling costs all need to be take into account. Other issues such as compatibility with existing components, operating gesture of a user are also to be considered. Moreover, a hand-held electronic device with a metal chassis may shield the millimeter-wave signal when the transceiver module inside it adopted an traditional planar patch array antenna. Therefore, it is required to provide an opening on the metal chassis above the antenna array for providing a path for electromagnetic wave propagation, which may smear the appearance of the hand-held electronic device. In addition, the beam direction of the patch array antenna disposed in the circuit board of the device is approximately perpendicular to the circuit board in the device. When the user operates the hand-held electronic device with normal holding position, the millimeter wave signal is transmitted towards the ground. Or, when two of the hand-held electronic devices are placed on a desktop for inter-device data transmission, the beam directions of the two devices are both towards the desktop instead of aiming each other. Therefore, the electromagnetic wave may not be effectively transceived, or unable to be transceived for the worst case. Moreover, when the user holds the hand-held electronic device, the patch array antenna disposed under a back lid of the hand-held electronic device is prone to be blocked by a hand portion of the user to reduce signal transceiving efficiency.